The field of the invention relates to illuminated electric switches having a pivotal operating handle, such as tab switches, toggle lever switches, rocker switches, etc., and specifically to means for guiding and directing light, emitted from a stationary source inside the switch housing, through the handle to concentrate the light at the external tip of the handle.
Switches having an externally extending handle pivotally mounted to a housing and illuminated by a light source within the housing are known in the art. Many of these switches have a translucent handle entirely illuminated. In some applications, it is desirable to have only a portion of the handle illuminated, for example, to distinguish it from other switch handles on a panel, or to illuminate only that part of the switch having indicia marked thereon, or to provide a smaller but more intense region of illumination on the handle rather than the lesser intensity of illumination of the whole handle when illuminated, or to readily identify the outermost tip of the handle, etc.
Some switches have used flexible light cables extending through the handle, but these switches suffer the disadvantage of fatigue of the cable after repeated pivoting of the handle. Some switches have a transparent cap or lens placed over the end of a hollow opaque handle, but these switches suffer the disadvantage of low intensity of illumination because only a small portion of light emanating from the source within the housing reaches the lens, most of the light being lost through dispersion and scattering.
Other disadvantages of prior switches include difficulty of relamping; for example, some switches cannot be relamped from the front or can only be relamped with special tools or by removing a bezel or mounting place.
While these prior devices have been useful for their intended purposes, the present invention relates to improvements thereover.